Apparatus for forming holes



Oct. 17, 1961 BECKMAN 3,004,320

APPARATUS FOR FORMING HOLES Filed June 8, 1959 2 Sheets-Sheet 1 Oct. 17, 1961 E. BECKMAN 3,004,320

APPARATUS FOR FORMING HOLES 2 Sheets-Sheet 2 Filed June 8, 1959 dway'ci x fienkmr-e United StaWS Patent 3,004,320 APPARATUS FOR FORMING HOLES Edward L. Beckman, Chicago, Ill. (515 Summit, Parkridge, Ill.) Filed June 8, 1959, Ser. No. 818,942 2 Claims. (Cl. 25-128) This invention relates to the formation of a hole in a body of material such as concrete and the primary object of the invention is to provide a novel hole forming system and apparatus which, compared to similar prior systems and apparatus, is easier to employ with a resulting saving inlabor cost, is less expensive, and insures the formation of a cylindrical holewithout concrete entering a mold for the hole.

A further object is to utilize as a mold for the hole a cylindrical core member having one end constructed in a novel manner for accurate location with respect to a form for the concrete body and closed at its other end by a cover for strengthening the member against collapse and preventing the flow of concrete into the member.

Other objects and advantages of the invention will become apparent from the following description taken in connection with the accompanying drawings in which:

FIGURE 1 is a fragmentary perspective view showing the positioning of novel apparatus embodying the present invention, an operator being shown schematically;

FIG. 2 is an exploded sectional view taken on a vertical plane and showing a core member about to be positioned on a locating pin;

FIG. 3 is a plan view of the core member without the cover;

FIG. 4 is a view similar to FIG. 2 and showing the core member in final position on the pin;

FIG. 5 is an exploded elevational view showing the fastening elements and the driving means therefor in relation to the finally positioned core member;

FIG. 6 is a plan view of the core member with the fastening elements in place;

FIG. 7 is an exploded perspective view showing the cover about to be inserted into the finally positioned core member;

FIG. 8 is a sectional view through the slab and the core member; and

FIG. 9 is a view similar to FIG. 8 with the form and core member removed.

The improved apparatus illustrated in the drawings is especially suited for the formation of a cylindrical hole 10 in a body such as a slab 11 of concrete (FIGS. 8 and 9), the hole receiving objects like a pipe 12, for example, Where the slab is to be a floor of a building. The slab usually is formed by at least partially enclosing the space for the slab with a form 13 and then filling the space with concrete which is poured into the form while flowable and is permitted to harden before the form is removed. In the present instance, the form is a horizontal sheet of wood supported in a suitable manner beneath the space for the slab. The hole may be blind with one end closed or, as shown in the drawings, may extend completely through the slab.

In general, the invention contemplates the provision of a core member 14 of cylindrical shape having one end open and its other end 15 closed but formed with a central aperture 16 centered on the axis of the member. To locate the member easily and accurately in a desired position with respect to the form 13, a locating pin 17 is secured in the form and is projected through the aperture. The use of such a pin is made possible while insuring that the core member remains secured to the form during the pouring of the concrete by driving through the closed end, from the interior of the member and into the is inserted into the open end'after the fasteners are inplace. After the concrete has been poured with the core member in place and has hardened, the form is taken away and the core member moveswith the form and axially out of the hole. f

Preferably and to insure further the accuracy of location of the core member 14 with respect to the form 13, the locating pin 17 is secured to the form before it is pro jected through the aperture 16 of the closed end 15 of the core. In the present instance, the pin is simply a nail driven upwardly through the form from its underside and having its pointed shank projecting upwardly beyond the upper side of the sheet. If desired, a plurality of such pins may be driven through the form for individual location of a plurality of core members as shown in FIG. 1.

For simplicity in procurement and use of the headed fasteners 18, these parts also are nails. Driving of the nails through the closed end 15 of the core member 14 and into the form from the interior of the member is effected with a hollow cylindrical guide 21 and a driving rod 22. The internal diameter of the guide is slightly larger than that of the nail heads and the driving rod so that the latter may telescope within the guide and engage the heads of nails within the guide so as to urge the nails ahead of it. An enlargement 23 on one end portion of the rod provides a handle to facilitate manipulation of the rod.

The cylindrical core member 14 preferably is a can of the commercially available type with the one closed end 15 and with the opening 24 in the other end sized to receive a standard cover 20. The latter is formed with a peripheral flange 25 telescoping and fitting snugly within the defining edge of the opening.

In operating the apparatus, each locating pin 17 first is projected through the form sheet 13. Next, the core member 14 is located accurately with respect to the form simply by telescoping the closed end 15 of the member over the pin to project the pin through the centered aperture 16. Nails 18 then are driven through the closed end from the interior of the core member by inserting the guide 21 into the member, depositing each nail in the guide with its pointed end down, and reciprocating the driving rod 22 within the guide and against the head 19 of the nail. Once the nails are in place to secure the core member to the form, the guide is removed and the cover 20 is pressed into place. The parts then are ready to receive the concrete 11 in a fiowable state, the cover 20 strengthening the open end of the core member against lateral pressures from the concrete and preventing entry of the concrete into the member. When the concrete is hardened, the form sheet is pulled away from the underside of the slab and, with it, the core member is pulled axially through and out of the hole 10 leaving the hole free as shown in FIG. 9.

It will be apparent that the novel apparatus utilizes parts which are readily available commercially and thus are less expensive than specially machined parts. Moreover, these parts may be used by unskilled labor to locate the holes 10 accurately and in a short time thereby reducing labor costs. The formation of the core member with the removable cover 20 is advantageous in enabling the fasteners 18 to be driven through the closed end 15 of the member and still provide the strengthening and closure of the open end 24 of the core member.

I claim:

1. In apparatus for use in forming a slab of concrete with a cylindrical hole, the combination of, a form enclosing at least a part of a space to be filled with said concrete, a hollow cylindrical member having one end open and its other end closed but formed with a small aperture centered on the axis of the member, a locating pin secured in said form and projecting rigidly therefrom through said aperture so as to locate the member ac-' curately with respect to the form, a plurality of fasteners having individual heads and projecting into said form from the interior of said cylindrical member to bring the heads thereon into engagementwith said closed end of the memflowable concrete poured into the form.

2. In apparatus for use in forming a slab of concrete with a cylindrical hole, the combination of, a form enclosing at least a part of a space to be filled with saidcon-i crete, a hollow cylindrical member having an end open 4 and its other end closed but formed with a small aperture centered on the axis of the member, a locating pin secured in said form and projecting rigidly therefrom through said aperture so as tolocate the member accurately with respect to the form, and a cover fitting into said one end of said cylindrical member to reinforce the member from collapse transaxially and to close the end to avoid entry into the member of flowable concrete poured into the form.

References Cited in the file of this patent. v UNITED STATES PATENTS 1,746,696

Ford et a1 "'Dec. 30, 1958 

